Theorem canthwdom 9539

Description: Cantor's Theorem, stated using weak dominance (this is actually a stronger statement than canth2 9100, equivalent to canth 7344). (Contributed by Mario Carneiro, 15-May-2015.)

Assertion

Ref	Expression
canthwdom	⊢ ¬ 𝒫 𝐴 ≼* 𝐴

Proof of Theorem canthwdom

Dummy variables 𝑥 𝑓 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		0elpw 5314	. . . . 5 ⊢ ∅ ∈ 𝒫 𝐴
2		ne0i 4307	. . . . 5 ⊢ (∅ ∈ 𝒫 𝐴 → 𝒫 𝐴 ≠ ∅)
3	1, 2	mp1i 13	. . . 4 ⊢ (𝒫 𝐴 ≼* 𝐴 → 𝒫 𝐴 ≠ ∅)
4		brwdomn0 9529	. . . 4 ⊢ (𝒫 𝐴 ≠ ∅ → (𝒫 𝐴 ≼* 𝐴 ↔ ∃𝑓 𝑓:𝐴–onto→𝒫 𝐴))
5	3, 4	syl 17	. . 3 ⊢ (𝒫 𝐴 ≼* 𝐴 → (𝒫 𝐴 ≼* 𝐴 ↔ ∃𝑓 𝑓:𝐴–onto→𝒫 𝐴))
6	5	ibi 267	. 2 ⊢ (𝒫 𝐴 ≼* 𝐴 → ∃𝑓 𝑓:𝐴–onto→𝒫 𝐴)
7		relwdom 9526	. . . . 5 ⊢ Rel ≼*
8	7	brrelex2i 5698	. . . 4 ⊢ (𝒫 𝐴 ≼* 𝐴 → 𝐴 ∈ V)
9		foeq2 6772	. . . . . . 7 ⊢ (𝑥 = 𝐴 → (𝑓:𝑥–onto→𝒫 𝑥 ↔ 𝑓:𝐴–onto→𝒫 𝑥))
10		pweq 4580	. . . . . . . 8 ⊢ (𝑥 = 𝐴 → 𝒫 𝑥 = 𝒫 𝐴)
11		foeq3 6773	. . . . . . . 8 ⊢ (𝒫 𝑥 = 𝒫 𝐴 → (𝑓:𝐴–onto→𝒫 𝑥 ↔ 𝑓:𝐴–onto→𝒫 𝐴))
12	10, 11	syl 17	. . . . . . 7 ⊢ (𝑥 = 𝐴 → (𝑓:𝐴–onto→𝒫 𝑥 ↔ 𝑓:𝐴–onto→𝒫 𝐴))
13	9, 12	bitrd 279	. . . . . 6 ⊢ (𝑥 = 𝐴 → (𝑓:𝑥–onto→𝒫 𝑥 ↔ 𝑓:𝐴–onto→𝒫 𝐴))
14	13	notbid 318	. . . . 5 ⊢ (𝑥 = 𝐴 → (¬ 𝑓:𝑥–onto→𝒫 𝑥 ↔ ¬ 𝑓:𝐴–onto→𝒫 𝐴))
15		vex 3454	. . . . . 6 ⊢ 𝑥 ∈ V
16	15	canth 7344	. . . . 5 ⊢ ¬ 𝑓:𝑥–onto→𝒫 𝑥
17	14, 16	vtoclg 3523	. . . 4 ⊢ (𝐴 ∈ V → ¬ 𝑓:𝐴–onto→𝒫 𝐴)
18	8, 17	syl 17	. . 3 ⊢ (𝒫 𝐴 ≼* 𝐴 → ¬ 𝑓:𝐴–onto→𝒫 𝐴)
19	18	nexdv 1936	. 2 ⊢ (𝒫 𝐴 ≼* 𝐴 → ¬ ∃𝑓 𝑓:𝐴–onto→𝒫 𝐴)
20	6, 19	pm2.65i 194	1 ⊢ ¬ 𝒫 𝐴 ≼* 𝐴

Syntax hints:  ¬ wn 3   ↔ wb 206   = wceq 1540  ∃wex 1779   ∈ wcel 2109   ≠ wne 2926  Vcvv 3450  ∅c0 4299  𝒫 cpw 4566   class class class wbr 5110  –onto→wfo 6512   ≼^* cwdom 9524

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-10 2142  ax-11 2158  ax-12 2178  ax-ext 2702  ax-sep 5254  ax-nul 5264  ax-pr 5390  ax-un 7714

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1543  df-fal 1553  df-ex 1780  df-nf 1784  df-sb 2066  df-mo 2534  df-eu 2563  df-clab 2709  df-cleq 2722  df-clel 2804  df-nfc 2879  df-ne 2927  df-ral 3046  df-rex 3055  df-rab 3409  df-v 3452  df-dif 3920  df-un 3922  df-in 3924  df-ss 3934  df-nul 4300  df-if 4492  df-pw 4568  df-sn 4593  df-pr 4595  df-op 4599  df-uni 4875  df-br 5111  df-opab 5173  df-mpt 5192  df-id 5536  df-xp 5647  df-rel 5648  df-cnv 5649  df-co 5650  df-dm 5651  df-rn 5652  df-iota 6467  df-fun 6516  df-fn 6517  df-f 6518  df-fo 6520  df-fv 6522  df-wdom 9525

This theorem is referenced by:  pwdjudom  10175